Antidepressant-Like Effect of Traditional Medicinal Plant Carthamus Tinctorius in Mice Model through Neuro-Behavioral Tests and Transcriptomic Approach

Major depression disorder (MDD) has become a common life-threatening disorder. Despite the number of studies and the introduced antidepressants, MDD remains a major global health issue. Carthamus tinctorius (safflower) is traditionally used for food and medical purposes. This study investigated the chemical profile and the antidepressant-like effect of the Carthamus tincto-rius hot water extract in male mice and its mechanism using a transcriptomic analysis. The antidepressant effect of hot water extract (50 mg/kg and 150 mg/kg) was investigated in mice versus the untreated group (saline) and positive control group (fluoxetine 10 mg/kg). Hippocampus transcriptome changes were investigated to understand the Carthamus tinctorius mechanism of action. The GC-MS analysis of Carthamus tinctorius showed that hot water extract yielded the highest amount of oleamide as the most active ingredient. Neuro-behavioral tests demonstrated that the safflower treatment significantly reduced immobility time in TST and FST and improved performance in the YMSAT compared to the control group. RNA-seq analysis revealed a significant differential gene expression pattern in several genes such as Ube2j2, Ncor1, Tuba1c, Grik1, Msmo1, and Casp9 related to MDD regulation in 50 mg/kg safflower treatment as compared to untreated and fluoxetine-treated groups. Our findings demonstrated the antidepressant-like effect of safflower hot water extract and its bioactive ingredient oleamide on mice, validated by a significantly shortened immobility time in TST and FST and an increase in the percentage of spontaneous alternation.